To determine how much sealer you'll need, measure the length and width of the area to be sealed. The amount of sealer used will depend on the particular material being sealed. For example, to seal a wet-poured cement-based paver you will need 1 litre per 7 sq.m. (1 quart per 70 sq.ft. per quart) and for sandstone you will need 1 litre per 4 sq.m. (1 quart per 40 sq.ft. per quart). Typical total application rate.